We have been doing single engine taxi for over 10 years without incident.
Not a big deal to do. If you are heavy you start out with a turn towards the non running engine and that avoids large loads on the tires and nose gear.
Not much work to do it.
A 320, to start second engine:
yellow hyd pump OFF
X bleed Auto (usually there anyways)
IGN selector to start
engine master ON
To shut it down taxiing in
Yellow pump ON
Engine master OFF